/*
* Copyright (c) 2021 hittun
* github url: https://github.com/hittun/opengl_game_template
* gittee url：https://gitee.com/hittun/opengl_game_template
* blog url: https://blog.csdn.net/hunter_wyh
*/
#include "hittun.h"

void error_callback(int errorcode, const char * description);
void framebuffer_size_callback(GLFWwindow *window, int width, int height);
void processInput(GLFWwindow *window);

int main()
{
	glfwSetErrorCallback(error_callback);
	// glfw: initialize and configure
	// ------------------------------
	glfwInit();
	glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
	glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
	glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
#ifdef __APPLE__
	glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE); //uncomment this statement to fix compilation on OS X
#endif
	// glfw window creation
	// --------------------
	GLFWwindow *window = glfwCreateWindow(WINDOW_SCR_WIDTH, WINDOW_SCR_HEIGHT, WINDOW_SCR_TITLE, NULL, NULL);
	if (window == NULL)
	{
		std::cout << "Failed to create GLFW window" << std::endl;
		glfwTerminate();
		return -1;
	}
	glfwMakeContextCurrent(window);
	// glad: load all OpenGL function pointers
	// ---------------------------------------
	if (!gladLoadGLLoader((GLADloadproc)glfwGetProcAddress))
	{
		std::cout << "Failed to initialize GLAD" << std::endl;
		return -1;
	}
	// InitHotKeyMgr();
	// render loop
	// -----------
	while (!glfwWindowShouldClose(window))
	{
		// input
		// -----
		processInput(window);

		// render
		// ------
		glClearColor(0.2f, 0.3f, 0.3f, 1.0f);
		glClear(GL_COLOR_BUFFER_BIT);

		// glfw: swap buffers and poll IO events (keys pressed/released, mouse moved etc.)
		// -------------------------------------------------------------------------------
		glfwSwapBuffers(window);
		glfwPollEvents();
	}
	// glfw: terminate, clearing all previously allocated GLFWresources.
	//---------------------------------------------------------------
	glfwTerminate();
	return 0;
}

void error_callback(int errorcode, const char * description)
{
	std::cout << "glfw error_callback errorcode:" << errorcode << ", description:"<< description << std::endl; 
}

void processInput(GLFWwindow *window)
{
	if (glfwGetKey(window, GLFW_KEY_ESCAPE) == GLFW_PRESS)
		glfwSetWindowShouldClose(window, true);
}

// glfw: whenever the window size changed (by OS or user resize) this callback function executes
// ---------------------------------------------------------------------------------------------
void framebuffer_size_callback(GLFWwindow *window, int width, int height)
{
	// make sure the viewport matches the new window dimensions; note that width and
	// height will be significantly larger than specified on retina displays.
	glViewport(0, 0, width, height);
}